<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Jun 15, 2016 at 11:57 AM, Laura Perez Cerrato <span dir="ltr"><<a href="mailto:lauraperezcerrato@gmail.com" target="_blank">lauraperezcerrato@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <br><div dir="ltr">Thanks to you all :) Should I commit those?</div></blockquote><div><br></div><div>I did already I think. But next time it'll be up to you ;-)</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="gmail_extra"><br clear="all"><div><div data-smartmail="gmail_signature"><div dir="ltr"><font size="2" face="arial, helvetica, sans-serif" color="#000000">-Laura Perez Cerrato</font></div></div></div>
<br><div class="gmail_quote">On 15 June 2016 at 15:56, David T. Lewis <span dir="ltr"><<a href="mailto:lewis@mail.msen.com" target="_blank">lewis@mail.msen.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Done.<br>
<br>
Thanks Laura!<br>
<br>
Dave<br>
<br>
<br>
> Hi David, Hi All,<br>
><br>
> I'd like Laura to be added as a committer to <a href="http://source.squeak.org/VMMaker" rel="noreferrer" target="_blank">source.squeak.org/VMMaker</a>.<br>
<div><div>><br>
> On Wed, Jun 15, 2016 at 7:28 AM, Laura Perez Cerrato <<br>
> <a href="mailto:lauraperezcerrato@gmail.com" target="_blank">lauraperezcerrato@gmail.com</a>> wrote:<br>
><br>
>><br>
>> Hello everyone,<br>
>><br>
>> Working on JPEGReadWriter2 I noticed that both reading and writing<br>
>> primitives include a sanity check that ensures that the<br>
>> source/destination<br>
>> Smalltalk bitmap has the exact size in bytes needed, instead of checking<br>
>> that its size is at least that needed. Some BitBlt primitives perform<br>
>> the<br>
>> same check, thus not allowing operations with forms with associated<br>
>> bitmaps<br>
>> with a size greater than needed.<br>
>><br>
>> When performing operations with images, and specially when such images<br>
>> are<br>
>> large in size, actually processing the images takes a small fraction of<br>
>> the<br>
>> time it takes to perform the whole operation, while allocating and<br>
>> deallocating correctly sized bitmaps takes much longer. If one would<br>
>> wish<br>
>> to process a series of similarly sized images (with a definite maximum<br>
>> size), it would be desirable to allocate a bitmap big enough to hold any<br>
>> of<br>
>> them only once and then reuse it, thus avoiding the aforementioned cost.<br>
>> Checking that source and destination bitmaps are big enough instead of<br>
>> checking that their size is exactly that which is expected would allow<br>
>> that<br>
>> optimization.<br>
>><br>
>> A brief exploration of BitBlt and JPEGReadWriter2's code, accompanied<br>
>> with<br>
>> some experimenting of what would happen if such sanity checks were<br>
>> modified<br>
>> as proposed, has lead me to thinking that these changes would be<br>
>> benefitial. I haven't observed any undesirable side effects (meaning,<br>
>> nothing seems to have blown up :)). However, I'm inexperienced in<br>
>> working<br>
>> with the VM, so it's rather expectable that I miss something :) Your<br>
>> input<br>
>> on the topic would be extremely appreciated.<br>
>><br>
>> The attached changesets contain the proposed set of changes.<br>
>><br>
>> Cheers!<br>
>><br>
>> -Laura Perez Cerrato<br>
>><br>
>><br>
><br>
><br>
</div></div><span><font color="#888888">> --<br>
> _,,,^..^,,,_<br>
> best, Eliot<br>
><br>
<br>
<br>
</font></span></blockquote></div><br></div>
<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><span style="font-size:small;border-collapse:separate"><div>_,,,^..^,,,_<br></div><div>best, Eliot</div></span></div></div></div>
</div></div>